Hydraulic construction



July 10, 1928.

G. W. BUNGAY HYDRAULIC CONSTRUCTION Filed Jan. 22, 1926 m N E V m Patented July 10, 1928.

UNITED STATES 1,676,249 PATENT OFFICE.

GEORGE W. BUNGAY, OF PLAINFIELD, NEW JERSEY, ASSIGNOR .TO DIE- OASTING CORPORATION, OF GARWOOD, NEW JERSEY, A CORPORATION 01' NEW JERSEY.

HYDRAULIC consrnuc'rxou.

Application filed January 22, 1926. Serial No. 82,910.

This invention relates to die casting machines, and more particularly, to such machines which are designed for casting relarotatlon serve to move the entlre die cartively large objects. Hitherto, certain pracb tical difliculties have presented themselves in the design of the larger machines. The cylinder employed for containing the piston to operate the movable die head has been an expensive part, particularly where the piston is operated by steam or compressed necessitates a smaller piston head, and furinvention is to provide means for applying thermore by providing novel and improved means for operating the piston by hydraulic pressure.

Another and more specific object of my difl'erent degrees of pressure to the piston to operate it in opposite directions. When the die heads are being forced together during the casting operation, a relatively great forceis needed to actuate the piston. whereas, a relatively small force is needed for mov-. ing the piston in the opposite direction to separate the heads.

In the accompanying drawing in which I have shown a selected embodiment of my invention. the figure"'shows a side elevation of a machine constructed according to my invention. parts being broken away and parts being shown in section for the sake of clearness.

The machine which I have shown is similar to that disclosed and claimed in. my Patent No. 1.279.650. September 24. 1918. This machine comprises a melting not 1. of

usual construction, and above which is supported a tilting pressure chamber 2. on trunnions 3. These trunnions may be? conveniently made hollow for the introduction of compressed air into the compression chamber. as is known in the art. A suitable toggle arrangement 4 provides means for tilting the pressure chamber. this toggle arrangementbeing actuated by rotation of the shaft 5.

Supported upon a fire box 6 and standard 7 is a frame 8. This frame comprises a plurality of rods supporting sliding bearings 9 which are connected by a web or plate 10. which in turn suppfdrts a die carriage 11 and and carriage accommodate dies of difierv ent sizes, the rods 8 are provided with racks 13 cooperating with pimons 14 which upon ria e. A suitable handle 15 may be provi ed for the operation of these pinions.

The cylinder and carriage are pivotally mounted upon the frame at 16, and the forward end of the combined carriage.v and cylinder is pivotally supported upon a bearing 17 adapted to slide upon a guide rod 18. The die carriage is also provided witha suitable adjusting means 19, whereby it may be adjusted for varying widths of dies.

Slidably mounted in the cylinder 12 is the piston comprising the piston rod 20 and the piston head 21. It will be-seen that the piston rod is,relativelylarge in diameter and that the; piston head is only slightly larger in,,diameter than the piston rod, and, therefore, a shoulder 22 is formed between the piston' rod and head.

Secured to one end of thelinder 12 are a plurality of rods 23 upon which the carriage 11 is slidable. At the extreme outer or left hand end of these rods is secured a die head 24 carrying a fixed die 25. Cooperating with the fixed die 25 is a movable die 26,ca rried by the die head 27. Thecarriagelland the movable die head arid die aresecured together and operated along the rods 23 by means of the movement pf the pis- @1120 which is secured to the carriage. It will be understood by those skilled in the art that, as the carriage and associated parts move toward the right, the entire structure will he lifted by rotation about the pivot 16 due to the eoaction ofthe bearing 17 with the guide rod 18. It will also be understood by those skilled in the art that the nozzle 28, when in its raised position. is slightly above the level of the metal in the melting pot and registers with an aperture 29 between the two dies 25 and 26.

A suitable' air control device indicated generally at 30 and operated by a handle 31 is used to control the passage of air to the pressure chamber 2 to force metal through the nozzle 28. The details of this construction form no part of my present invention and need not be described further. To provide hydraulic pressure for theoperation of the piston I supply two connections, one discharging through the port 32 its cylinder 12, I rd rto ov th fr 1 into the end of the cylinder 12 and thdother discharging through the port 33 adjacent the point Where the shoulder 22 comes in contact with a shoulder 34 in the c lind er. A suitable assage 35 is provider? in the shoulder 34 wiiereby the hydraulic pressure may be exerted against the shoulder 22 on the piston head. These two connections, formed by the pipes 36 and 37 respectively, lead to a valve 38, which may be of any suitable and well-known construction, and which controls the passage of fluid from the inlet 39 to the pipes 36 and 37 and also controls the release 40. The details of this valve form no part of my invention and need not be described. A suitable handle 41 may be employed to control the operation of the valve. It is obvious that the pipes 36 and 37 act as inlets and also as exhausts, as the case may be.

In operation the valve 38 is manipulated so as to admit hydraulic pressure to the cylinder either at 32 or 33, as the case may be, and it will be evident that the pressure exerted by the fluid entering the cylinder at 32 will be much greater and will cause a positive bringing together of the two dies and a positive holding of them in position for casting. By using hydraulic pressure it is possible to employ a much smaller cylinder than when using steam or compressed air. Moreover. the use of hydraulic pressure provides a positive means for actuating the piston and which is not present when a compressible fluid, such as air or steam, is used. This positive means provides a lock to hold together the dies against the pressure of the metal which is forced between the dies. At the same time by applying the releasing force along the comparatively narrow shoulder, the amount of energy employed is conserved. Moreover, as the piston rod moves through the cylinder, it is evident that it will take up a substantial portion of the space therein, so that the amount of area upon which hydraulic pressure is to be exerted remains small. This results in a great economy in the operation of the machine and makes it a practical commercial device.

I understand that it is possible to vary construction of my machine within wide limits without departing from the scope of my invention, and I do not intend to limit myself except by the appended claims.

I claim:

1. A die-casting machine comprising two dies, one movable in respect to the other, a piston connected to said movable die and reciprocating in a cylinder, said piston having a head in said cylinder forming a shoulder with the piston rod, said cylinder having a shoulder cooperating with the shoulder on said piston, said shoulder in the cylinder having a port therethrough for the application of hydraulic pressure to the shoulder on said piston, and said cylinder having a port adjacent its other end for the application of pressure to the other face of said iston.

2. die-casting machine comprising two dies, one movable in respect to the other, a piston connected to said movable die and reciprocating in a cylinder, said piston having a head in said cylinder forming a shoulder with the piston rod, said cylinder having a shoulder cooperating with the shoulder on said piston, said shoulder in the cylinder having a port therethrough for the application of hydraulic pressure to the shoulder on said piston, said cylinder having a port adjacent its other end for the application of pressure to the other face of said piston, and a valve controlling both of said ports.

In testimony whereof, I have affixed my signature to this specification.

GEORGE W. BUNGAY.

- CERTIFICATE OF CORRECTION.

Patent No. 1,676,249.

Granted July 10, 1928, to

GEORGE W. BUNGAY.

It is hereby certified that th of New Jersey,

I e above numbered patent was erroneously issued to Aluminum Die-Casting Corporation, of Garwood, New Jersey,

whereas said patent should have been issued to Aluminum Company", a Corporation of Pennsylvania, assignee by mesne assignments of the entire interest a Corporation "The United States said corporation beingin said invention; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Signed and sealed this 31st day of July,

(Seal) Office. A D. 1928.

M. J. Moore, Acting Commissioner of Patents.

discharging through the port 33 adjacent the point Where the shoulder 22 comes in contact with a shoulder 34 in the c lind er. A suitable assage 35 is provider? in the shoulder 34 wiiereby the hydraulic pressure may be exerted against the shoulder 22 on the piston head. These two connections, formed by the pipes 36 and 37 respectively, lead to a valve 38, which may be of any suitable and well-known construction, and which controls the passage of fluid from the inlet 39 to the pipes 36 and 37 and also controls the release 40. The details of this valve form no part of my invention and need not be described. A suitable handle 41 may be employed to control the operation of the valve. It is obvious that the pipes 36 and 37 act as inlets and also as exhausts, as the case may be.

In operation the valve 38 is manipulated so as to admit hydraulic pressure to the cylinder either at 32 or 33, as the case may be, and it will be evident that the pressure exerted by the fluid entering the cylinder at 32 will be much greater and will cause a positive bringing together of the two dies and a positive holding of them in position for casting. By using hydraulic pressure it is possible to employ a much smaller cylinder than when using steam or compressed air. Moreover. the use of hydraulic pressure provides a positive means for actuating the piston and which is not present when a compressible fluid, such as air or steam, is used. This positive means provides a lock to hold together the dies against the pressure of the metal which is forced between the dies. At the same time by applying the releasing force along the comparatively narrow shoulder, the amount of energy employed is conserved. Moreover, as the piston rod moves through the cylinder, it is evident that it will take up a substantial portion of the space therein, so that the amount of area upon which hydraulic pressure is to be exerted remains small. This results in a great economy in the operation of the machine and makes it a practical commercial device.

I understand that it is possible to vary construction of my machine within wide limits without departing from the scope of my invention, and I do not intend to limit myself except by the appended claims.

I claim:

1. A die-casting machine comprising two dies, one movable in respect to the other, a piston connected to said movable die and reciprocating in a cylinder, said piston having a head in said cylinder forming a shoulder with the piston rod, said cylinder having a shoulder cooperating with the shoulder on said piston, said shoulder in the cylinder having a port therethrough for the application of hydraulic pressure to the shoulder on said piston, and said cylinder having a port adjacent its other end for the application of pressure to the other face of said iston.

2. die-casting machine comprising two dies, one movable in respect to the other, a piston connected to said movable die and reciprocating in a cylinder, said piston having a head in said cylinder forming a shoulder with the piston rod, said cylinder having a shoulder cooperating with the shoulder on said piston, said shoulder in the cylinder having a port therethrough for the application of hydraulic pressure to the shoulder on said piston, said cylinder having a port adjacent its other end for the application of pressure to the other face of said piston, and a valve controlling both of said ports.

In testimony whereof, I have affixed my signature to this specification.

GEORGE W. BUNGAY.

- CERTIFICATE OF CORRECTION.

Patent No. 1,676,249.

Granted July 10, 1928, to

GEORGE W. BUNGAY.

It is hereby certified that th of New Jersey,

I e above numbered patent was erroneously issued to Aluminum Die-Casting Corporation, of Garwood, New Jersey,

whereas said patent should have been issued to Aluminum Company", a Corporation of Pennsylvania, assignee by mesne assignments of the entire interest a Corporation "The United States said corporation beingin said invention; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Signed and sealed this 31st day of July,

(Seal) Office. A D. 1928.

M. J. Moore, Acting Commissioner of Patents. 

